Electrical connection



March 7, 1950 H. D. SECREST ELECTRICAL CONNECTION Filed July 9, 1946 HOYLI, BWITT Patented Mar. 7, 1950 UNITED STATES PATENT OFFICE ELECTRICAL CONNECTION Hoyle D. Secrest, Washington, D. 0., assignor to John F. Nusser, Washington, D. 0.

Application July 9, 1946, Serial No. 682,387

2 Claims. 1

This invention relates to an electrical connection. While the structure is of general utility, it has particular usefulness in the construction of a thermal regulator.

In devices such as thermal regulators or the mercury column type, the mercury column is contacted by electrical leads spaced apart along the length of the column, said leads extending through the glass walls of the tube containing the mercury column. The mounting for the thermal regulator consists of a collar through which binding posts extend. Finely drawn wires are soldered to the binding posts and to the leads contacting the mercury column, respectively. Dilliculty has been experienced in devices of this character in that the structure is not strong enough to withstand the twisting off of the wires extending between the binding post and the leads as the thermal regulator is being placed in position, or being changed from one installation to another.

It is an object of this invention to construct a mounting for a thermal regulator, including the electrical connections, which is rugged enough to withstand handling without breaking the electrical connections. A further object of the invention is to construct a mounting and an electrical connection for a thermal regulator which is easily and quickly assembled.

Generally, these objects are obtained by providing a collar comprising a pair of semi-cylindrical segments which is adapted to fit about the tube containing the mercury column. The bind ing posts are fixed against displacement in this collar. ner ends of the binding posts and to the leads to the mercury column, and the collar is firmly bound in place upon the tube by metal rings and a filling of cement. This results in a very rugged structure which is easily assembled and which can be handled without fear of the twisting and breaking of the delicate wires connecting the binding posts to the mercury leads.

'The means by which the objects of the invention are obtained are more fully described with respect to the accompanying drawings in which:

Figure 1 is the top plan View of a thermal regulator embodying the invention;

Figure 2 is a side-elevational view of the regulator shown in Figure l.

Figure 3 is a cross-sectional view on the line 3-3, Figure 1;

Figure 4 is a side-elevational view of one of the half-segments of the collar with a binding post mounted thereon;

Connecting wires are soldered to the in Figure 5 is an enlarged cross-sectional view on the line 55, Figure' i; and

Figure 6 is an enlargement of a part of the cross-sectional view shown in Figure 3.

As shown in Figures 1 and 2, the thermal regulator consists of a mercury thermometer tube 2 having a mercury column 4 therein, said mercury column extending from a mercury bulb 6 at the lower end of the tube 2 to an expansion chamber 8 at the upper end of the regulator, said expansion chamber having a globule of mercury I 9 therein. The tube 2 is surrounded by a mounting 12 which includes an electrically insulating collar section [4 through which extend binding posts It and I8 respectively, and metal rings 25 and 22 surrounding the upper and lower portions of the collar. A protecting glass tube 24 fits over the upper end of the thermal regulator and down into the mounting 12.

As shown in detail in Figures 3 and 6, glass tube 2 has extending thereinto two spaced leads 26 and 28, which leads contact the inner channel of the tube through which the mercury column 4 extends. It is to be understood that when the lower end of the regulator is immersed in a cold substance, the mercury column drops below the lead 26, thus breaking any electrical conducting connection between the leads 26 and 28, and when the temperature surrounding the bulb 6 rises, the mercury column 4 rises and completes an electrical conducting connection between the leads 26 and 28. 1

Wires 30 and 32 are soldered, respectively, to the outer ends of leads 26 and 28, and are soldered, respectively, to binding posts l6 and I8. Collar segments 14 are bored to form ports 31 through which the binding posts extend.

In order to prevent the binding posts from being displaced with a consequent breaking of the wires 30 and 32, each binding post is provided with a pin 34, note Figure 5, which extends transversely of the binding post and projects therefrom into a socket 36 formed in the collar l4.

As previously stated, the mounting I2 is composed of a pair of semi-cylindrical collar segments l4. As shown in Figures 4 and 6, each segment is composed of an enlarged central section 40, an upper reduced section 42, and a lower reduced section 44. The inner surface of section 42 extends midway of section 49 to form a shoulder 46 which forms a seat for the glass tube 24. The inner portion of section 44 is of sufiiciently greater area than tube 2 so that a filling of cement 48 can be interposed between the tube and 3 the collar inv order to secure the tube in place in the mounting.

The device is assembled as follows: After the tube 2 has been formed, including the leads 2% and 28, the wires 39 and 32 are soldered to the leads and to the binding posts, respectively. The tube, with the binding posts attached thereto, is then laid upon one of the segments It and the binding posts 16 and is are set into the bores 31 with their pins 3d projecting into the holes 36. The other semi-cylindrical segment is then placed in position to complete the collar and the two segments M are pressed together to firmly seat pins 34 into the holes 36. Rings 29 and 22 are then fastened over the portions 42 and M of the segments to securely bind the segments together. Cement 48 is then poured into the space between segment portion 44 and tube 2, thus completing the mounting l2 and holding the collar firmly in position upon tube 2. Glass tube 24 is then inserted over the upper end of the tube and seated upon the shoulder 6 to complete the assembly.

Actual experience with this mounting has demonstrated that it is very inexpensively constructed and assembled while, at the same time, it is sufficiently rugged so that the electrical connection between the binding posts and the mercury column is not broken due to the dislocation or breaking of the wires 36 and 32 while the regulator is being installed or being handled in changing it from one installation to another. In particular, it has been discovered that the pins 39 will hold the binding posts rigidly in place up to the point that the binding posts themselves are mutilated before the wires 39 and 32 are being disturbed.

Having now described the means by which the objects of my invention have been obtained, I claim:

1. An electrical connection for a mercury tube thermal regulator comprising a mercury regulator tube, a pair of electrically insulating semicylindrical segments surrounding said tube, spaced ring elements engaging said segments and forming them into a collar, binding posts eX- tending through said collar, cement means securing said collar to said tube, and means for electrically connecting said binding posts to the mercury column in said tube.

2. An electrical connection as in claim 1 in which said binding posts extend through the joint between said pair of segments, and including means for preventing said binding posts from being displaced relative to said segments.

HOYLE D. SECREST.

REFERENCES CITED The following references are of record in the file or" this patent:

UNITED STATES PATENTS Number Name Date 776,026 Jacobson Nov. 29, 1904 1,073,336 English Sept. 16, 1913 1,113,125 Johnson Oct. 6, 1914 1,171,852 Klein Feb. 15, 1916 1,674,253 Lightfoot June 19, 1928 2,079,800 Grant May 11, 1937 2.24:8,759 Hollander July 8, 1941 FOREIGN PATENTS Number Country Date 683,085 Germany Dec. 18, 1939 

